The invention relates to internal combustion engines, and more particularly, to internal combustion engine piston ring constructions.
It is common practice in the design of internal combustion engines to install a pin in an engine piston to prevent rotation of a piston ring mounted on the piston, relative to the piston. Piston rings have opposite ends spaced apart to form a gap which allows mounting of the piston rings on pistons. The pins are provided in the pistons of prior art internal combustion engines to prevent the piston rings from rotating to a position where they can deflect into intake or exhaust ports of the internal combustion engine, especially when the engine is a high performance engine having large intake or exhaust ports.
The practice of installing a pin in a piston for preventing rotation of a piston ring is costly as is the associated practice of forming a notch in the piston ring, to accept the pin, in such a fashion that a reasonably small piston ring can be produced having a minimal gap between the spaced apart opposite ends, when the piston ring is mounted on the piston. In addition to being costly, these practices have been known to reduce total engine reliability.
Attention is directed to the following U.S. patent references:
______________________________________ Flammang 1,363,725 December 28, 1920 Smith 1,514,022 November 4, 1924 Hof 1,526,309 February 10, 1925 Phillips 2,428,177 September 30, 1947 Block 2,955,579 October 11, 1960 Yost 3,379,186 April 23, 1968 Lassanske 3,554,564 January 12, 1971 Fukui 4,256,067 March 17, 1981 Irimajiri et al. 4,256,068 March 17, 1981 Thomas et al. 4,286,501 September 1, 1981 Lassanske 4,367,702 January 11, 1983 Irimajiri et al. 4,383,508 May 17, 1983 Honda 4,471,730 September 18, 1984 Tanaka et al. 4,474,144 October 2, 1984 Irimajiri et al. 4,502,434 March 5, 1985 Tomita et al. 4,671,228 June 9, 1987 ______________________________________
Attention is also directed to U.S. Winston patent application No. 035,596, and to the following foreign references:
______________________________________ Dawson Australia 17,848/29 January 14, 1929 Bonfa Great Britain 441,224 January 15, 1936 Levesque France 1,156,722 May 20, 1958 ______________________________________